The isolation and purification of esterase 1 from the cytosol of rabbit neutrophils will be pursued further. The study of the activation of other membrane enzymes of the neutrophil particularly by formyl-methionine peptides will be investigated. The studies of cation transport in neutrophils induced by chemotactic factors will be further pursued. We will also further explore the nature and function of the receptor on the neutrophil membrane that reacts with synthetic chemotactic factors.